coils

[Fred Jones]

Hello all,
Is there any information on how to make professional quality coils. It seems that the projects and kits that I have seen for PI detectors have you wind turns of wire and say nothing about how to do sheilding. Nor have I seen info on what a double D is, how to make it, why it works, how to sheild it, pictures or diagrams, etc. If anyone knows of a source, I would appreciate it. Thanks for any help,
Fred

[Carl]

A double-D coil has two same-size coils that overlap. Sometimes they are in the shape of a "D". But think about any two coils - if you overlap them then at some point the inductive coupling goes to near-zero. This is what you want for IB or 2-coil PI.

Winding a coil is not too hard. I've built a winding machine (3"-24" capacity) with turns counter that I need to photograph and write up. Shielding is fairly easy, wrap the coil in wire or foil almost all the way around. Alignment is tough no matter what style coil. I need to look into how to mount the coils, i.e., casting or whatever. Looking for ideas on this.

- Carl

[graeme]

Hi Fred,

I invite you to E-Mail me; are you interested in Pulse Induction or a particular circuit/kit? I recently posted my latest thoughts on coils on the Treasure P.I. Forum - about three weeks ago - no responses followed, so its nice to see someone thinking in this regard.

graeme

[m w]

if anyone has any further info on coils please email me. as I too am building my own MD and I am unfamiliar with what works best. So any pitfalls to avoid would be greatly appreciated.

thank you
mark w

[Joe]

Hi,
I'm very interested in the same answers to the questions asked. I'd like to build a DD or Ib for my Bounty Hunter as a first project. Any drawings,explanations on shielding and setting the coil up would be appreciated! Joe jnorrell@tds.net